Inventories, Net - Inventories, Net (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Inventory [Line Items]
Total raw materials	$ 3,358	$ 2,941
Total work-in-process	12,155	11,771
Total finished goods	3,653	3,636
Total inventories, net	19,166	18,348
Security Products
Inventory [Line Items]
Total raw materials	2,542	2,134
Total work-in-process	9,721	9,138
Total finished goods	2,376	2,582
Marine Components
Inventory [Line Items]
Total raw materials	816	807
Total work-in-process	2,434	2,633
Total finished goods	$ 1,277	$ 1,054